It is reasonable to say that cloud computing evolved from and typically (but not always) depends on grid computing. Grid computing requires software (such as Condor) to schedule and prioritize jobs and is of particular importance to system administrators. Cloud computing adds a layer of services on top of the grid that are of particular interest to the end-user consumer. However, clouds may run on servers that are not part of any official grid. These servers must typically be very powerful if they are intended to serve many users.

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